Really enjoy the STEN. Great for catching or floating in a putt from 70 feet away on a calm day. I love the K4 plastic! Totally different than their others, more sticky and lightweight. Personally I'd love to see a few more of their molds in this plastic. Always exiciting when Kastaplast releases new molds/plastic. It won't replace the TUFF or REKO in my bag, but something fun to warm up with before you play! 

Its a lightweigh Berg, kind of. I was surprised how shallow this disc was. The shape is that of a Berg but slightly more shallow and feels like its a smaller diameter. I thought this was going to be just another 1 speed high glide catch disc like all the others, good or bad, it is not. It is light weight 130g , flies straight with a slight fade at the end.  All in all I guess it's fine but I think falls short of all the other catch discs on the market.
My biggest complaint with this disc is the new K4 plastic. It is aweful. It feels like one of those rubber balls you get from a vending machine at the grocery store, its sticky and feels like it is going to just come apart at the first rick or tree hit. 
Personally I hope they never make another disc in this plastic.